Chromia-based brick

Abstract

A chromia-based brick, having chromia as a main component, includes: 70 to 95 mass % of Cr 2 O 3 ; 0.5 to 15 mass % of ZrO 2 ; 0.4 to 4.0 mass % of P 2 O 5 derived from phosphate added as raw material; 10 or lower mass % of Al 2 O 3 ; and a sintering aid component and unavoidable components.

What is claimed is: 
     
         1 . A chromia-based brick, having chromia as a main component, comprising:
 70 to 95 mass % of Cr 2 O 3 ;   0.5 to 15 mass % of ZrO 2 ;   0.4 to 4.0 mass % of P 2 O 5  derived from phosphate added as raw material;   10 or lower mass % of Al 2 O 3 ; and   a sintering aid component and unavoidable components.   
     
     
         2 . A chromia-based brick, having chromia as a main component, comprising:
 75 to 95 mass % of Cr 2 O 3 ;   0.5 to 14 mass % of ZrO 2 ;   1.5 to 3.0 mass % of P 2 O 5  derived from phosphate added as raw material;   8 or lower mass % of Al 2 O 3 ; and   a sintering aid component and unavoidable components.   
     
     
         3 . The chromia-based brick according to  claim 2 , wherein the phosphate includes aluminum phosphate. 
     
     
         4 . The chromia-based brick according to  claim 3 , wherein one or two selected from a group consisting of: zirconia-mullite having a grain diameter of 0.1 to 3 mm; and baddeleyite having a grain diameter of less than or equal to 0.074 mm, are used as the raw material of ZrO 2 . 
     
     
         5 . The chromia-based brick according to  claim 4 , wherein a porosity is 10 to 20%. 
     
     
         6 . The chromia-based brick according to  claim 5 , wherein said chromia-based brick is used in a region, in which corrosion resistance is requested, in a waste-melting furnace, pig-iron equipment, gasification furnace for organic substance, and glass-melting furnace. 
     
     
         7 . A chromia-based brick, having chromia as a main component, comprising:
 88 to 98 mass % of Cr 2 O 3 ; and   1.5 to 3.0 mass % of P 2 O 5  derived from phosphate added as the raw material;   10 or lower mass % of Al 2 O 3 ; and   a sintering aid component and unavoidable components.   
     
     
         8 . The chromia-based brick according to  claim 7 , wherein the phosphate includes aluminum phosphate.